[Diagnosis of posterior spinal artery infarctions using diffusion-weighted MRI]

Posterior spinal artery (PSA) infarctions are rare and challenging to diagnose in the acute phase. Herein, we report two cases of PSA infarctions diagnosed using spinal diffusion-weighted imaging-MRI (DWI-MRI). Case 1 involved a 74-year-old male patient presenting to our hospital with right leg numbness and unsteadiness while walking. Neurological examination revealed muscle weakness in the right lower limb and decreased vibration sensation in the dermadrome below the right Th8 level. Spinal DWI-MRI showed a high-intensity signal in the posterior right Th8, leading to the diagnosis of thoracic spinal cord infarction in the PSA region. In Case 2, a 70-year-old woman visited our hospital complaining of numbness of the left hand. Neurological examination revealed left-sided paresthesia exhibiting a positive Romberg's sign. Spinal DWI-MRI showed a high-intensity signal in the right C2 level posterior region, confirming the diagnosis of cervical spinal cord infarction in the PSA region. A neurological examination for PSA infarction and highlights the usefulness of a spinal cord DWI for auxiliary diagnosis.